<pre>  /**
   * The constants used in this Content Widget.
   */
  public static interface CwConstants extends Constants {
    String[] cwRadioButtonColors();

    String cwRadioButtonDescription();

    String cwRadioButtonName();

    String cwRadioButtonSelectColor();

    String cwRadioButtonSelectSport();

    String[] cwRadioButtonSports();
  }

  /**
   * An instance of the constants.
   */
  private final CwConstants constants;

  /**
   * Initialize this example.
   */
  @Override
  public Widget onInitialize() {
    // Create a vertical panel to align the radio buttons
    VerticalPanel vPanel = new VerticalPanel();
    vPanel.add(new HTML(constants.cwRadioButtonSelectColor()));

    // Add some radio buttons to a group called 'color'
    String[] colors = constants.cwRadioButtonColors();
    for (int i = 0; i &lt; colors.length; i++) {
      String color = colors[i];
      RadioButton radioButton = new RadioButton("color", color);
      radioButton.ensureDebugId("cwRadioButton-color-" + color);
      if (i == 2) {
        radioButton.setEnabled(false);
      }
      vPanel.add(radioButton);
    }

    // Add a new header to select your favorite sport
    vPanel.add(new HTML("&lt;br&gt;" + constants.cwRadioButtonSelectSport()));

    // Add some radio buttons to a group called 'sport'
    String[] sports = constants.cwRadioButtonSports();
    for (int i = 0; i &lt; sports.length; i++) {
      String sport = sports[i];
      RadioButton radioButton = new RadioButton("sport", sport);
      radioButton.ensureDebugId(
          "cwRadioButton-sport-" + sport.replaceAll(" ", ""));
      if (i == 2) {
        radioButton.setValue(true);
      }
      vPanel.add(radioButton);
    }

    return vPanel;
  }

</pre>